block: Null pointer dereference in blk_root_get_parent_desc()

[mirror_qemu.git] / gdbstub.c

diff --git a/gdbstub.c b/gdbstub.c
index f1d51480f79d3604f5089a6684066e21740081f3..c4e4f9f08219ddfd6be5dfe28d50d171bff987d4 100644 (file)
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -20,7 +20,6 @@
 #include "qapi/error.h"
 #include "qemu/error-report.h"
 #include "qemu/cutils.h"
-#include "cpu.h"
 #include "trace-root.h"
 #ifdef CONFIG_USER_ONLY
 #include "qemu.h"
@@ -507,6 +506,7 @@ static inline int tohex(int v)
         return v - 10 + 'a';
 }
 
+/* writes 2*len+1 bytes in buf */
 static void memtohex(char *buf, const uint8_t *mem, int len)
 {
     int i, c;
@@ -674,6 +674,16 @@ static const char *get_feature_xml(const char *p, const char **newp,
         }
         return target_xml;
     }
+    if (cc->gdb_get_dynamic_xml) {
+        CPUState *cpu = first_cpu;
+        char *xmlname = g_strndup(p, len);
+        const char *xml = cc->gdb_get_dynamic_xml(cpu, xmlname);
+
+        g_free(xmlname);
+        if (xml) {
+            return xml;
+        }
+    }
     for (i = 0; ; i++) {
         name = xml_builtin[i][0];
         if (!name || (strncmp(name, p, len) == 0 && strlen(name) == len))
@@ -999,8 +1009,8 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
     const char *p;
     uint32_t thread;
     int ch, reg_size, type, res;
-    char buf[MAX_PACKET_LENGTH];
     uint8_t mem_buf[MAX_PACKET_LENGTH];
+    char buf[sizeof(mem_buf) + 1 /* trailing NUL */];
     uint8_t *registers;
     target_ulong addr, len;
 
@@ -1547,6 +1557,12 @@ void gdb_do_syscallv(gdb_syscall_complete_cb cb, const char *fmt, va_list va)
     *p = 0;
 #ifdef CONFIG_USER_ONLY
     put_packet(s, s->syscall_buf);
+    /* Return control to gdb for it to process the syscall request.
+     * Since the protocol requires that gdb hands control back to us
+     * using a "here are the results" F packet, we don't need to check
+     * gdb_handlesig's return value (which is the signal to deliver if
+     * execution was resumed via a continue packet).
+     */
     gdb_handlesig(s->c_cpu, 0);
 #else
     /* In this case wait to send the syscall packet until notification that
@@ -1803,7 +1819,7 @@ void gdb_signalled(CPUArchState *env, int sig)
     put_packet(s, buf);
 }
 
-static void gdb_accept(void)
+static bool gdb_accept(void)
 {
     GDBState *s;
     struct sockaddr_in sockaddr;
@@ -1815,17 +1831,19 @@ static void gdb_accept(void)
         fd = accept(gdbserver_fd, (struct sockaddr *)&sockaddr, &len);
         if (fd < 0 && errno != EINTR) {
             perror("accept");
-            return;
+            return false;
         } else if (fd >= 0) {
-#ifndef _WIN32
-            fcntl(fd, F_SETFD, FD_CLOEXEC);
-#endif
+            qemu_set_cloexec(fd);
             break;
         }
     }
 
     /* set short latency */
-    socket_set_nodelay(fd);
+    if (socket_set_nodelay(fd)) {
+        perror("setsockopt");
+        close(fd);
+        return false;
+    }
 
     s = g_malloc0(sizeof(GDBState));
     s->c_cpu = first_cpu;
@@ -1834,6 +1852,7 @@ static void gdb_accept(void)
     gdb_has_xml = false;
 
     gdbserver_state = s;
+    return true;
 }
 
 static int gdbserver_open(int port)
@@ -1846,9 +1865,7 @@ static int gdbserver_open(int port)
         perror("socket");
         return -1;
     }
-#ifndef _WIN32
-    fcntl(fd, F_SETFD, FD_CLOEXEC);
-#endif
+    qemu_set_cloexec(fd);
 
     socket_set_fast_reuse(fd);
 
@@ -1876,7 +1893,11 @@ int gdbserver_start(int port)
     if (gdbserver_fd < 0)
         return -1;
     /* accept connections */
-    gdb_accept();
+    if (!gdb_accept()) {
+        close(gdbserver_fd);
+        gdbserver_fd = -1;
+        return -1;
+    }
     return 0;
 }
 
@@ -2016,7 +2037,11 @@ int gdbserver_start(const char *device)
             sigaction(SIGINT, &act, NULL);
         }
 #endif
-        chr = qemu_chr_new_noreplay("gdb", device);
+        /*
+         * FIXME: it's a bit weird to allow using a mux chardev here
+         * and implicitly setup a monitor. We may want to break this.
+         */
+        chr = qemu_chr_new_noreplay("gdb", device, true);
         if (!chr)
             return -1;
     }
@@ -2052,6 +2077,13 @@ int gdbserver_start(const char *device)
     return 0;
 }
 
+void gdbserver_cleanup(void)
+{
+    if (gdbserver_state) {
+        put_packet(gdbserver_state, "W00");
+    }
+}
+
 static void register_types(void)
 {
     type_register_static(&char_gdb_type_info);